Radio signaling system



Sept. 16, 1930.

s. P. NIXDORFF ,7 5,826

RADIO SIGNALING SYSTEM Filed Nov. 15, 1927 3 Sheets-Sheet l Figz.

I \Z I a ,7 3 I l b B L Inventor": Samuel P. Nixdor,

p 1930. s. P. NIXDORFF RADIO SIGNALING SYSTEM 3 Sheets-Sheet 2 Fi1 ed Nov. 15'. 1927 Inventor: Samuel 1 NixdorH His Attorneg.

' Sept. 16, 1930.. s. P. NIXDORFF RADIO SIGNALING SYSTEM Filed Nov. 15. 1927 3 Sheets-Sheet 3 Inventor: Samuel T Nixclorff,

Hls Attorney.

Patented Sept. 16, 1939 UNETEE SAMUEL P. NIXDOR-FF, 0E $CEIEI IECTADY, HEW KC-BK, ASSIGNOE TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEIT YORK RADIO SEG- My invention relates to radio signaling systems and more particularly to radio signaling systems adapted for operation at short waves.

In a copending application of Ernst F. W. Alexanderson filed November 15, 1927, Serial N 0. 233,509 entitled Radio signaling systems and which is assigned to the same assignee as my present application there are disclosed antennae systems which are particularly adapted for radio signaling at short waves of one or more frequencies. Antennae constructed in accordance with the invention of the mentioned application comprise a plurality of conductors each of which includes a number of sections which are alternately arranged to form continuous parallel lines including sections of each conductor. The arrangement is such that each of the sections in each line constitute individual oscillating units all of which oscillate in phase and cooperate to project a wave in a certain direction. As thus arranged the antenna possesses etlicient radiating properties and it is highly directive in both the horizontal and vertical planes.

My present invention has for its purpose to effect certain improvements in antennae of the type mentioned and to provide antennze which have certain advantages over those of the prior art both in structural arrangement and in operation. More particularly my invention has for its purpose to provide antennae systems which embody certain features of the antennae mentioned and in which all of the different sections of the conducting members of the antenna cooperate to project or to respond to waves having a common direction. of propagation. Still another purpose of my invention is to provide a directive antenna .in which the direction in which the projected waves are propagated may be readily changed.

The novel features which I believe to be characteristic of my invention will be set LING EYSTEM Serial No. 233,491.

fo th with particularity in the appended claims. My invention itself, however, both as to its organization and method of operation together with further objects and advantages thereof may best be understood by reference to the following description taken in connection with the accompanying drawing in which the various figures represent diagrammatically dillerent embodiments of my invention.

In each of the figures the conducting members of the antenna are represented by heavy lines and the suspension cables and feeder conductors are represented by light lines. The necessary insulating members are represented as small rectangles except where per spective is employed in which case they are represented as circular disks.

Referring to the drawing Fig. l rc rescnts a simple form of an mna embodying my inxention. In are nil tower or mast w supporting the antenna.

tower 1 obliquely tow. or portion of which in for example, by 111V; as of a p anchors 3 3 driven into the ground and arranged in circular relation about the support 1. The antenna comprises a coinlucting member 4 which is arranged in Z' or staircase formation extending from top of the tower 1 pa allel with the suspension member 2. 'lms conducting member comprises two sets of sections, one of them 00 com the sections (1., 7), c which are arranged, for exan and the other com the sections (Z, c which are arranged a vertical plane. These sections are of equal length and the sections of each set are altcrnatel y arranged along the length of the conductor, the successive sections of one a, 7), c extendimr in difiierent directions from the inte 'iate section of the other set (Z, c. A. suitable c l. hall quired.

section of the antenna as, for example, the mid-section Z) is interrupted at the point 5 and atthis point is connected by means of feeder line 6 to a suitable highfrequency apparatus 7 which may be a transmitter, a receiver or both. When energized with high frequency currents having a wave length equal to twice the length of the equal sections of the antenna, the relative direction of the currents in the different sections of the antenna will be that indicated by the arrows. It will be seen that the horizontal sections a, b, c are energized in phase and-are adapted in themselves to project or to respond to waves having a horizontal polarization and )10 )a ated in a direction at ri ht angles to the plane of the antenna. Lilie- Wise the sections (Z, c are adapted in themselves to project or to respond to vertically polarized waves propagated at right angles to the plane of the antenna. The combined effect of the different sections is to project a wave at right angles totheplane ofthe antenna having a polarizationat as degrees upward as is indicated by the'arrow 8, and

similarly if used as a receiver to produce a. maximum response to waves having such polarization.

It will be seen that an antenna having the arrangement set out has very decided structural advantages. It comprises a directional antenna which may be supported by a single tower 1 and suspension cable 2 plus additional staywires, notshown, as may be re- At the same time the zigzag or staircase arrangement facilitates the matter of obtaining a high effective elevation of the antenna above the earth. If it be desired to change the direction of propaga tion ofthe waves projected from the an tenna, or towhich the antenna respond, this may be effected by moving the suspension cable 2 about the supportl to. the desired position such, for example, as that representedby the dotted lines 1, 2, 8 inthe drawing. Thus by the SllTlPlGOPGlEllJlOU of removing the cable 2 from one anchor 3 to-another anchor 3 and thereby rotating the antenna about the support-lthe direction'of propagation of the radiated waves may be changedto any point in the compass.

Fig. 2 shows an antenna of the form shown in Fig. 1 with the exception that the end sections f and g of the conducting llltBUk' 'ber are vertical rather than horizontal and the conducting member'is a wave length longer thanthat shown in the former fig-- This antenna will operate in the manure. ner set forth in F 1 but will bemore di-. rective in a vertical plane. The length'of V the antenna may be, of course, extended as desired with the limitation'that the more re mote sections should preferably be substantially" equally energized with the sections proximate to the feeder conductors. Like- .had.

wise an even number of sections may be employed.

In Fig. 3 another form of myinvention is shown employing two conductors 9 and 10 which are suspended between the supporting cable 2 and the tower 1 in a suitable manner. The conductor 9 is formed of the horizontal sections a, b, c and the vertical sections (Z, c and the conductor 10 is similarly formed of the sections a, b, 0, cl, 6, the'sectionse e, (Z 0, (5 cl, 0. 6 being arranged in continuous lines and conductors 9 and 10 being insulated from each other at the points 11 and 12. A suitable section of each conductor, such as the mid-sections, 1) and Z) are each interrupted and the two sections are there connected together by means of feed lines 13, the midpoint of which is connected to thehigh frequency apparatus 7 such. that the conductors 9 and 10 respond to waves propagated at a right angle to the plane of the antenna and having a plane of polarization at 45 degrees to the vertical.

Fig. 4, Fig. 5 and Fig. 6 represent further embodiments of my invention in which a group arrangement of the conductors 1s employed. In each of these figures, a group of conductors 14, 14 are each constructed in a are arran 'ed in a45 degree relation to each' other, and in Fig. .6 they are arranged in a vertical direction. Thus variations in the directive properties of the antenna may be For example, the arrangement shown in Fig. .6 will project a wave having greater directivity in the verticalplane than that shown in Fig. 4, whereas the antenna shown in Fig. 4 will be more directive in the horizontal plane than that shown in Fig. 6. By the arrangement shown in Fig. 5 equal di-l rectivity in both planes may be expec ed.

In each of the Figs. 4, 5 and 6 the midpoints of the feeder l1nes' 3 are connected through j lines of equal electrical length to'the high frequency apparatus 7 or through lines so arranged that proper phase relations in the different conductors is had. This may be secured by adjusting the length of the conductors or by the insertion of artificial means such as concentrated inductance or capacity. In Fig. 7 I haveshown another form of my invention in which one v group of conductors 14, such as represented in Fig. 8, is suspended from one side of thetower '1 and Thus it will be seen' another group 14 is suspended upon diametrically opposite sides of the tower 1, these groups being electrically equidistant from the high frequency apparatus 7 The general direction of these antennae as indicated by the lines 21, 22 is at right angles to each other, consequently if these be energized with currents having a 90 degree phase relation between the two a circularly or elliptically polarized wave will be projected at right angles to the plane of the antenna. This phase relation may be effected by connecting suitable phase adjusting means 17, 18 in the feeder leads 19 and 20 or by adjusting the length of the feeder wires as desired. With an arrangement of antenna such as that shown in Figs. 7 and 8 horizontally and vertically polarized waves may be projected alternately. Thus, for example, if the two groups of antennae 14 and 14' are energized in phase the horizontal members will cooperate to project a horizontally polarized wave at right angles to the plane of the antenna, whereas the vertical members of the group 14 will be opposed to the vertical members of the group 14 with the result that their effects will be neutralized in a direction at right angles to the plane of the antenna. f the phase relation of the currents in the group 14 now be reversed the vertical members will cooperate to project a vertically polarized wave in a direction at right angles to the plane of the antenna, whereas the horizontal members will be pposed in this direction. This phase reversal between the currents in the groups 14 and 14 may be suitably etlected by electrical means if desired or by a mechanical device, such as a reversing switch 23 connected in the leads to one of the groups. The type of antenna shown in Figs. 7 and 8 may be of particular utility in connection with the reduction of fading, as has been pointed out in a copending application of Ernst F. lV. Alexanderson, filed November 15, 1927, Serial No. 238,508 and which is assigned to the same assignee as my present invention.

Figs. 9 and show additional modifications of my invention in which the antenna are suspended in a vertical plane between the towers 24; and 25, the different sections of each conducting member being disposed at degrees, or other suitable angle, to the vertical and one conducting member being arranged directly above the other to form continuous parallel lines in the manner set out in connection with the other figures. These antennae will project a vertically polarized wave propagated at right angles to the plane of the antenna.

Fig. 11 shows a still difierent embodiment in which the groups of antennae are suspended in a horizontal plane between supporting members 24 and 25. This antenna will proj set a. horizontally polarized Wave vertically upward and shouldtherefore have particular utility in connection with the direction of airplanes.

Thus with an arrangement of conductors such as those described an antenna is formed in which all of the conducting sections of the antenna cooperate to project or to respond to waves of a desired character. The different parallel sections are operable in phase and this is effected without the use of concentrated inductance, capacity or tuning means of any kind which will interfere with the operation of the antenna at a plurality of frequencies. Any suitable length of conductor may be em ployed but where long antenna are desired it is preferable to employ those of the type shown in Figs. 4, 5, 6, 9 and 11 since in these antennae all sections may be substantially equally energized.

If desired suitable reflectors constructed in a manner similar to the construction of the antenna may be arranged in proximity to the antenna as set out in the above application Serial No. 233,509 of Ernst F. V. Alexanderson.

While I have shown particular embodiments of my invention it will, of course, be understood that I do not wish to be limited thereto since many modifications of the arrangements shown and described may be made without departing from the spirit and scope of my invention as set forth in the appended claims.

VVhat I claim as new and desire to secure by Letters Patent of the United States is:

1. In combination, an antenna comprising a conductor formed of two sets of alternately arranged sections, each of said sets comprising a plurality of substantially equal parallel sections separated by intermediate sections, the sections of one set being at an angle to the sections of the other set and adjacent sections of both sets extending in opposite directions from the intermediate section of the other set, a second similar conductor arranged in space relation with said first conductor to form a substantially continuous line comprising sections of both conductors, high frequency apparatus adapted for operation at a wave length approximately equal to twice the length of said substantially equal sections and lines connecting said apparatus and each of said conductors whereby all of the sections in each line cooperate in phase.

2. In combination, an antenna comprising a conductor formed of two sets of alternately arranged sections, each of said sets comprising a plurality of substantially equal parallel sections separated by intermediate sections, the sections of one set being at an angle to the sections of the other set and adjacent sections of both sets extending in opposite directions from the intermediate section of the other set, a second similar conductor arranged inspace relation with said first conductor to form substantially continuous parallel lines extending in different directions, each of said llnes comprlslng sectlonsof both conductors,

high frequency apparatus adapted for operation at awavelength approximately equal to tWicethe length of said substantially equal sections and lines "connecting" said apparatus and said Conductors whereby all of the sections in said parallel lines cooperate in phase.

In Witness whereof, I have hereunto set my hand this 14th day of November, 1927.

SAMUEL P. NIXDORFF;

CERTIFICATE or CORRECTION.

Patent No. 1,775,826. Granted September 16, 1930, to

SAMUEL P. NIXDORFF.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, line 76, for

"dc" read bc; and that the said Letters Patent should be read with this correetion therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 28th day of October, A. D. 1930.

M. J. Moore,

(Seal) Acting Commissioner of Patents. 

